DC/DC converter arrangements are widely used for up-conversion of a supply voltage or down-conversion of a supply voltage to generate an output voltage for a circuit. For example, DC/DC converter arrangements are used in devices for mobile communication and digital cameras. DC/DC converters used for down-conversion are, for example, buck mode converters, whereas DC/DC converters for up-conversion are, for example, boost converters. If the supply voltage is nearly about the same as the output voltage, then DC/DC converter arrangements operating in a buck-boost mode can be used.
Document U.S. Pat. No. 6,717,388 B2 shows a buck converter with two switches and one inductor, a boost converter with two switches and one inductor, and a fly-back converter with two switches and one inductor.
Document U.S. Pat. No. 5,402,060 refers to a buck-boost converter with one inductor, two switches, and two diodes.
In the document by B. Sahu, G. A. Rincón-Mora, “A Low Voltage, Dynamic, Non-inverting, Synchronous Buck-Boost Converter for Portable Applications”, IEEE Transactions on Power Electronics, Vol. 19, No. 2, March 2004, pp. 443-452, a buck-boost DC/DC converter having one inductor and four switches is presented. Two of the four switches are on during a first phase of a control cycle, while two other switches are on during a second phase of the control cycle. These two phases are repeated periodically.